A number of prior art systems and methods have been developed in an attempt to increase the reliability, predictability, and maintainability of industrial machine tools to achieve consistent product quality and machine productivity goals in high-volume production environments. These systems and methods typically focus on monitoring primary machine components such as motors and spindles under idle conditions. However, due to the complex interaction of various machine components, fixturing, workpiece variability, and the operating environment, among others, a systematic and comprehensive system and method for characterizing such machines and processes is needed.
One approach to detecting and correcting problems in a complex system, such as an industrial machine tool, is to monitor the major machine components such as the spindles, motors, pumps, and the like, in an attempt to isolate suspect components. Mechanical signature analysis techniques have been utilized to monitor relative distributions in the frequency domain of a vibration signal to identify pending failures. A number of advanced techniques particularly suited for detecting abnormalities in rotating machines, and for implementing process control in manufacturing environments have also been developed. However, such isolated characterization of machine components has proven to be inadequate as an indicator of long-term reliable performance of industrial machine tools.
As discussed in "Machine Condition Signature Analysis for Reliability and Maintainability Improvement," written by the inventors of the present invention and published in the Proceedings of the International Programmable Controls Conference in April, 1993, the disclosure of which is hereby incorporated by reference in its entirety, it is desirable to characterize not only the individual elements of a particular machine tool, but also the interactions between these elements and the operating environment, which often includes various other operating machine tools. While that paper discloses a methodology for applying mechanical signature analysis techniques to characterize the interactions between various machine elements, it does not provide a generic, systematic method and associated system which characterizes machine components, structure, tooling, fixtures, and the workpiece as an integral system.